From: Varun Sethi <Varun.Sethi@freescale.com>
Date: Tue, 24 Jun 2014 13:57:15 +0000 (+0530)
Subject: iommu/fsl: Fix PAMU window size check.
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d033f48f3a4a9279c7475891fbb060d4881c22da;p=linux-beck.git

iommu/fsl: Fix PAMU window size check.

is_power_of_2 requires an unsigned long parameter which would
lead to truncation of 64 bit values on 32 bit architectures.

__ffs also expects an unsigned long parameter thus won't work
for 64 bit values on 32 bit architectures.

Signed-off-by: Varun Sethi <Varun.Sethi@freescale.com>
Tested-by: Emil Medve <Emilian.Medve@Freescale.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
---

diff --git a/drivers/iommu/fsl_pamu.c b/drivers/iommu/fsl_pamu.c
index b99dd88e31b9..bb446d742a2d 100644
--- a/drivers/iommu/fsl_pamu.c
+++ b/drivers/iommu/fsl_pamu.c
@@ -170,10 +170,10 @@ int pamu_disable_liodn(int liodn)
 static unsigned int map_addrspace_size_to_wse(phys_addr_t addrspace_size)
 {
 	/* Bug if not a power of 2 */
-	BUG_ON(!is_power_of_2(addrspace_size));
+	BUG_ON((addrspace_size & (addrspace_size - 1)));
 
 	/* window size is 2^(WSE+1) bytes */
-	return __ffs(addrspace_size) - 1;
+	return fls64(addrspace_size) - 2;
 }
 
 /* Derive the PAACE window count encoding for the subwindow count */
@@ -351,7 +351,7 @@ int pamu_config_ppaace(int liodn, phys_addr_t win_addr, phys_addr_t win_size,
 	struct paace *ppaace;
 	unsigned long fspi;
 
-	if (!is_power_of_2(win_size) || win_size < PAMU_PAGE_SIZE) {
+	if ((win_size & (win_size - 1)) || win_size < PAMU_PAGE_SIZE) {
 		pr_debug("window size too small or not a power of two %llx\n", win_size);
 		return -EINVAL;
 	}
@@ -464,7 +464,7 @@ int pamu_config_spaace(int liodn, u32 subwin_cnt, u32 subwin,
 		return -ENOENT;
 	}
 
-	if (!is_power_of_2(subwin_size) || subwin_size < PAMU_PAGE_SIZE) {
+	if ((subwin_size & (subwin_size - 1)) || subwin_size < PAMU_PAGE_SIZE) {
 		pr_debug("subwindow size out of range, or not a power of 2\n");
 		return -EINVAL;
 	}
diff --git a/drivers/iommu/fsl_pamu_domain.c b/drivers/iommu/fsl_pamu_domain.c
index 93072ba44b1d..3dd0b8edd429 100644
--- a/drivers/iommu/fsl_pamu_domain.c
+++ b/drivers/iommu/fsl_pamu_domain.c
@@ -301,7 +301,7 @@ static int check_size(u64 size, dma_addr_t iova)
 	 * Size must be a power of two and at least be equal
 	 * to PAMU page size.
 	 */
-	if (!is_power_of_2(size) || size < PAMU_PAGE_SIZE) {
+	if ((size & (size - 1)) || size < PAMU_PAGE_SIZE) {
 		pr_debug("%s: size too small or not a power of two\n", __func__);
 		return -EINVAL;
 	}